Yom tov sheni shel galuyot (Hebrew: יום טוב שני של גלויות‎), also called in short yom tov sheni, means "the second festival day in the Diaspora", and is an important concept in halakha (Jewish law). The concept refers to the observance of an extra day of Jewish holidays outside of the land of Israel.

Contents

The need for a second festival day arises from problems encountered by Jews living in the Diaspora following the Babylonian exile. The Jewish calendar, is a lunar system with months of 29 or 30 days. In Temple times, the length of the month depended on witnesses who had seen the new moon coming to the Temple in Jerusalem. Following confirmation of their evidence, a new Jewish month would be proclaimed. News of this proclamation was subsequently sent out to all Jewish communities. If no witnesses arrived, the new month was proclaimed the following day. Those communities who didn't receive word of the precise date of the beginning of the new month by the time of a festival, would keep the festival for two days, to account for the eventuality the new month wasn't proclaimed only the following day.[1]

The second day is observed for all Biblically-ordained festivals, with exceptions (see below).

Thus, Shavuot is one day in Israel and two days in the Diaspora. Pesach is a seven day festival in Israel, the first and last days of which are holy days, with five days of Chol HaMoed in between. In the Diaspora, it is an eight day festival, with a pair of holy days at the start and finish, and four days Chol HaMoed.

Sukkot is a seven-day festival in Israel, the first day of which is a holy day, followed by six days of Chol Hamoed. These are, in turn, followed immediately on the eighth day by the separate-but-related holy day of Shemini Atzeret. In the Diaspora, the first two days are holy days, and are followed by five days of Chol Hamoed. These are in turned followed by two holy days of Shemini Atzeret. However, in the Diaspora, the name "Shemini Atzeret" is used only to refer to the first of the two days; the second day is called Simchat Torah.

There are two exceptions to the rule. The fast day of Yom Kippur, which is one day even in the Diaspora, due to the difficulty of a two-day fast.[2] Also, Rosh Hashanah is two days even in Israel, because it falls on the first day of the month; thus, even Israelis would not find out the correct day until after the holiday.

^Furthermore, the previous month, Elul, virtually never had a full thirty days, so there was really no doubt as to when Yom Kippur would fall. Combined with the difficulty of a 48-hour fast, this is enough to declare Yom Kippur just one day. However, the other Tishrei holidays are observed for two days, despite the lack of doubt.